Field of the Invention
The present invention relates to a portable fluorescent X-ray analyzer used for a purpose of outdoor elementary analysis to be conducted in archaeological material search, criminal site investigation or fire initial investigation.
With a usual fluorescent X-ray analyzer, an object to be measured is contained within a sealed cover type sample chamber structure. Prevention against X-ray leaks to the outside of the apparatus is realized comparatively easily and reliably by such methods as checking the state of the sample chamber door. In the case of a portable fluorescent X-ray analyzer for frequent use at an unspecified, typically outdoor site on the other hand, X-ray radiation is completely open in the direction of the object to be measured. Consequently, in order to secure safety for the measurer or other persons that are around the fluorescent X-ray analyzer, it has been requisite for the measurer to pay careful attention to realize installation conditions which avoid exposure to X-rays. Usually when X-ray radiation is carried out, reference is made to the state of a plurality of sensors or switches provided on the fluorescent X-ray analyzer in determining whether the specified conditions necessary for the shutter to be safely opened are met. For example, the apparatus is structured so that the X-ray radiation is started only when the shutter operation release switch is turned on and also the lead switch is turned on by the contact of the lever of the lead switch mounted in the area beyond the X-ray radiation port of the fluorescent X-ray analyzer with one part of the sample to be measured. In order to maintain such a condition, a method has been adopted that a measuring head of the fluorescent X-ray analyzer is fixed to a precise position using a fixture such as a tripod. Further, safety is secured by obeying a procedure that the shutter operation release switch is turned off before carrying the fluorescent X-ray analyzer to a measurement site, and the measurer turns on this switch only when preparation for measurement is completed.
There are often cases that there is difficulty in placing a fluorescent X-ray analyzer in contact with one part of a sample to be measured during fixation of the analyzer at a measurement site. There are cases where contact is impossible because of the size or property of the sample to be measured. However, in the absence of such a safety mechanism, there may be a case that the installation conditions of the fluorescent X-ray analyzer are changed due to a blast of strong wind or such, resulting in accidental X-ray radiation to other points than the sample to be measured. The realization of a state in which the safety mechanism operates through fixing the position of the fluorescent X-ray analyzer makes installation difficult, lessening mobility of the portable fluorescent X-ray analyzer. However, there is a dilemma that the possibility increases of causing an X-ray exposure accident unless a safety mechanism is provided to enable measurement only under certain specified conditions.
It is an object of the present invention to obtain a portable fluorescent X-ray analyzer which solves the above problems and is high in safety and easy to handle.
In order to achieve the above object, the present invention has, in a fluorescent x-ray analyzer, image input means for optically reading the external appearance and the background of the sample to be measured, first storage means for storing image data acquired by the image input means, second storage means for storing related data to a figure previously registered, data comparing means for comparing data stored in the first storage means with data stored in the second storage means, state detecting means for detecting the installation state of the fluorescent X-ray analyzer, and x-ray switch means to control the shutter drive means correspondingly to outputs of the data comparing means and the state detecting means when a measurement start instruction is given.
The image input means optically reads a sample to be measured and the background in the vicinity thereof. An object of a specific shape is put in the vicinity of the sample to be measured and read by the image input means. The image data read at this time is stored in the first storage means. On the other hand, the second storage means stores data related to the above specific shape. The data comparing means determines whether or not image data corresponding to the specific shape is contained in the image data of the first storage means, based on the data of the second storage means. If the data is included, an activation signal is outputted to the X-ray switch means. The state detecting means outputs an activation signal to the X-ray switch means when detecting that the fluorescent X-ray analyzer is installed in a safe state. When the measurement start instructing means instructs that measurement start, the X-ray switch means examines signals from the data comparing means and state detecting means and controls the shutter drive means to open a shutter only in the case both are activating signals.